'12 FX4 screw with over 500 pounds of flaking rust...One of the two bolts on my driver side leaf spring just spins and spins and spins. Can't tighten it down or pull it out. Any help on how to get the damn thing out of there? Right now, I'd rather push the damn truck off a cliff. I'm guessing I need to remove the u bolts and work it out from the bottom? What risks am I taking not having that bolt tightened down?